This term, commonly used by college-age students, is someone you share a
house with (or, less commonly, an apartment).
These people were, to my knowledge, formerly known as "roommates," in virtually all contexts.
Housemate seems to be merely one of the many
trendy terms being tossed around these days.
Here are possible reasons for this word's existence:
A) Perhaps it's supposed to have less of the negative stigma that the word "roommate" seems to carry with it.
B) Also possible is that roommate implies a closer
relationship/friendship than simply housemate.
